More than two and a half years after it was announced at San Diego Comic Con 2013, two of the most iconic superheroes of all time are at last set to face off against one another when Batman V Superman: Dawn of Justice opens this week. For swathes of cinema-goers, its the stuff that dreams are made of. Few things stir up the over-eager imaginations of franchise fans more than the idea of two characters from hitherto disparate story worlds meeting up, and/or doing battle. Okay, so the Man of Steel and the Dark Knight have long co-existed in comic book and animated form, but never before now have they shared the screen in live action, making this a truly momentous occasion for anyone who even remotely cares for the characters. However, as we all know, this is far from the first time such established cinematic icons have gone toe-to-toe on the big screen. From Universals classic monsters of the 1940s, to Tohos kaiju of the 1960s, to some of the greatest slasher and sci-fi antagonists of the 1980s, weve seen many fan-pleasing, universe-sharing punch-ups over the decades. Yet, for most of this time, the format has typically been looked down upon as a trashy B-movie conceit. It wasnt until Marvel Studios broke the billion dollar mark with 2012s The Avengers that the notion of movie crossover universes gained some degree of respectability; and, rather more importantly, huge profitability. Previously considered a last ditch effort by studios running out of ideas to sell their most lucrative properties, crossover movies are now on the slate of almost all the major studios, with cinematic universe as the new buzz word. So why did it take so long for the notion of a shared story world take so long to gain critical and commercial acceptance? What mistakes did previous versus movies make which Batman V Superman had best do all it can to avoid? The following, for starters
